Effect of IgG3 Hinge Region Length Polymorphisms on Iron Fortification among Rural Pre-School Ghanaian Children and Its Associated Risk to Malaria and Anaemia.

Abstract

Sub-Saharan African pre-school children have an interdependence among immune response, infection resistance and adaptive effect of the dietary intake. However, the long hinge region of immunoglobulin G3 makes binding easy to malaria antigens and receptors, eliciting a more protective response among subclasses of immunoglobulin G. However, it is unknown if iron-containing multimicronutrients are associated with risk of anaemia and malaria in pre-school children with hinge region G3 immunoglobulin polymorphism living in high malaria transmission areas. We aimed to determine the impact of iron fortification in pre- chool children with immunoglobulin G3 hinge region length polymorphisms and their associated risk of malaria and anaemia in rural Ghana. This retrospective controlled, double blind, randomized population study was conducted over six months in rural Ghana among 6 to 35-month-old infants and young children. Participants were randomly allocated either ironfree multimicronutrients powder (placebo group) or iron (intervention group; 12.5 mg iron daily) into clusters where mixed semi-liquid homemade meals were delivered daily for 5 months. Anti-malaria mosquito bed nets and anti-malaria treatment were readily available during the study. Standardized therapeutic and epidemiological questionnaires were administered. Participants’ blood samples were assessed for immunoglobulin G3 hinge region length polymorphism, full blood count, anthropometry, and malaria microscopy. Baseline anthropometry, anaemia, iron status, demographic characteristics and dietary consumption were similar (p > 0.05). 27.85 % were venerable to clinical malaria at baseline. Homozygote medium polymorphism had the maximum frequency of 48 %, followed by homozygote long polymorphism (43 %), heterozygote long-medium polymorphisms (7.0 %) and relatively few were homozygote short 2.0 % with similarities between the study groups (p = 0.14; HardyWeinberg equilibrium estimate, χ2 analysis). However, iron fortification did not influence the risk of aneamia and malaria among participants with immunoglobulin G3 hinge region length polymorphisms but was not detrimental to participants.